I'm getting closer to finding a direct bolt-on, shorty front brake lever for my Baggy. I tried to modify a KTM lever (from the late 90s LC4), but the KTM master cylinder is apparently nothing like the Grimeca, because the "arm" that actuates the master cylinder plunger isn't even close.
I did find out that lots of trials guys use Grimeca M/Cs, so I've tried one that I thought was close. Here's a pic of it next to my (slightly bent - don't ask) stock:
The good news about this one is that it uses exactly the same adjuster screw (that goes through the bottom of the actuator arm and connects with the M/C plunger), and is clearly manufactured for a Grimeca M/C that is oh-so-close to the Baggy's.
The bad news is that, due to the very slight differences in geometry, I'm still not there. First, in order to get it to fit right, I had to grind about a mm off of the stopper end of the lever (blue arrow), which wasn't really so bad. However, even when I got that satisfactorily fitted, the actuator arm (red arrow) is a couple of millimeters short of the stock Baggy lever. This means that the adjuster screw that goes through the end of the arm doesn't quite line up with the M/C plunger.
The issue here is that the actuator arm and adjuster screw are moving on an arc, and the stock lever is engineered such that the screw meets the plunger at the bottom of its arc when the M/C is in the important part of its operation. Because of the shorter actuator arm on the modified lever, the angle is a little to steep when it meets the plunger.
I have the idea that I can "lengthen" the actuator arm on the new lever by cutting two small oval brackets (kind of like an "8" shape) and a sleeve between them to fit the end of the actuator arm. I.e., the "8's" get secured to either side of the actuator arm with a bolt/nut, and the adjuster screw goes through the bottom holes on the "8s" and the sleeve. Probably a lot of trouble for an imperfect setup, though.
Bottom line on this try: I made it fit, but it's far from ideal. This shorty allows me to fit my Acerbis Rallye Pro handguards without moving the M/C perch, but the ill-fitting lever (especially the short actuator arm) makes me worry about safety. I've still got it on, and the front brake is fully functional even under a hard squeeze, but the lack of a perfect match between arm and plunger still bothers me.
That said, I've searched and searched the internet to find anything close, and the best I've come up with is the above. Believe it or not, given the time that I've spent trying to find a solution, if I had to recommend a solution to someone, I'd say get a second stock lever and cut it. If you're decent at welding aluminum, maybe you can even cut out a section and weld the ball back onto the end for safety.
Another weird thing about my search is that, back in November, I test-rode a 2008 KTM 990 Adventure. As I laid my hand on the front brake and looked down at the lever, I could have sworn I was staring at my Baggy's front brake lever. It looked exactly the same. However, in my searches for an OEM replacement for the 2008 990 Adventure, the actuator arms on them (and in fact on all the KTMs with hydraulic front brakes) look way too short.
Oh, well. Hope some of that helps.